Optical lens, image capturing device and electronic device

ABSTRACT

An optical lens includes, in order from an object side to an image side, a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element and a sixth lens element. The first lens element with negative refractive power has an image-side surface being concave in a paraxial region thereof. The second lens element has refractive power. The third lens element has positive refractive power. The fourth lens element with positive refractive power has an image-side surface being convex in a paraxial region thereof. The fifth lens element with negative refractive power has an image-side surface being concave in a paraxial region thereof and including one convex shape in an off-axis region thereof. The sixth lens element with refractive power has an image-side surface being concave in a paraxial region thereof and including one convex shape in an off-axis region thereof.

RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.14/800,927, filed on Jul. 16, 2015, now U.S. Pat. No. 9,791,670, whichclaims priority to Taiwan Application Serial Number 104110961, filed onApr. 2, 2015, the entirety of which is incorporated by reference herein.

BACKGROUND Technical Field

The present disclosure relates to an optical lens and an image capturingdevice. More particularly, the present disclosure relates to a compactoptical lens and image capturing device applicable to electronicdevices.

Description of Related Art

In recent years, with the popularity of mobile terminals having camerafunctionalities, the demand of miniaturized optical systems has beenincreasing. The sensor of a conventional optical system is typically aCCD (Charge-Coupled Device) or a CMOS (ComplementaryMetal-Oxide-Semiconductor) sensor. As the advanced semiconductormanufacturing technologies have allowed the pixel size of sensors to bereduced and compact optical systems have gradually evolved toward thefield of higher megapixels, there is an increasing demand for compactoptical systems featuring better image quality.

A conventional optical system employed in a portable electronic productmainly adopts a four-element lens structure or a five-element lensstructure. Due to the popularity of mobile terminals with high-endspecifications, such as smart phones, tablet personal computers andwearable apparatus, the requirements for high resolution and imagequality of present compact optical systems increase significantly.However, the conventional optical systems cannot satisfy theserequirements of the compact optical systems.

Other conventional compact optical systems with six-element lensstructure enhance image quality and resolution. However, the arrangementof the lens elements thereof cannot provide both of the characteristicsof the wide field of view and the compact size for obtain the properaberration and relative illumination, thus the image quality thereofcannot be improved.

SUMMARY

According to one aspect of the present disclosure, an optical lensincludes, in order from an object side to an image side, a first lenselement, a second lens element, a third lens element, a fourth lenselement, a fifth lens element and a sixth lens element. The first lenselement with negative refractive power has an image-side surface beingconcave in a paraxial region thereof. The second lens element hasrefractive power. The third lens element has positive refractive power.The fourth lens element with positive refractive power has an image-sidesurface being convex in a paraxial region thereof, wherein anobject-side surface and the image-side surface of the fourth lenselement are aspheric. The fifth lens element with negative refractivepower has an image-side surface being concave in a paraxial regionthereof, wherein the image-side surface of the fifth lens elementincludes at least one convex shape in an off-axis region thereof, and anobject-side surface and the image-side surface of the fifth lens elementare aspheric. The sixth lens element with refractive power has animage-side surface being concave in a paraxial region thereof, whereinthe image-side surface of the sixth lens element includes at least oneconvex shape in an off-axis region thereof, and an object-side surfaceand the image-side surface of the sixth lens element are aspheric. Theoptical lens has a total of six lens elements with refractive power,there is an air space between every two lens elements of the first lenselement, the second lens element, the third lens element, the fourthlens element, the fifth lens element and the sixth lens element that areadjacent to each other. When a focal length of the first lens element isf1, a focal length of the second lens element is f2, an axial distancebetween the first lens element and the second lens element is T12, andan axial distance between the second lens element and the third lenselement is T23, the following conditions are satisfied:-0.20<|f1|/f2<1.50; and1.0<T12/T23.

According to another aspect of the present disclosure, an imagecapturing device includes the optical lens according to theaforementioned aspect and an image sensor, wherein the image sensor isdisposed on an image surface of the optical lens.

According to further another aspect of the present disclosure, anelectronic device includes the image capturing device according to theaforementioned aspect.

According to yet another aspect of the present disclosure, an opticallens includes, in order from an object side to an image side, a firstlens element, a second lens element, a third lens element, a fourth lenselement, a fifth lens element and a sixth lens element. The first lenselement with negative refractive power has an image-side surface beingconcave in a paraxial region thereof. The second lens element hasrefractive power. The third lens element has positive refractive power.The fourth lens element with positive refractive power has an image-sidesurface being convex in a paraxial region thereof, wherein anobject-side surface and the image-side surface of the fourth lenselement are aspheric. The fifth lens element with negative refractivepower has an image-side surface being concave in a paraxial regionthereof, wherein an object-side surface and the image-side surface ofthe fifth lens element are aspheric. The sixth lens element withpositive refractive power has an object-side surface being convex in aparaxial region thereof and an image-side surface being concave in aparaxial region thereof, wherein the image-side surface of the sixthlens element includes at least one convex shape in an off-axis regionthereof, and the object-side surface and the image-side surface of thesixth lens element are aspheric. The optical lens has a total of sixlens elements with refractive power, there is an air space between everytwo lens elements of the first lens element, the second lens element,the third lens element, the fourth lens element, the fifth lens elementand the sixth lens element that are adjacent to each other. When a focallength of the first lens element is f1, a focal length of the secondlens element is f2, a focal length of the fourth lens element is f4, anda focal length of the sixth lens element is f6, the following conditionsare satisfied:−1.50<|f1|/f2<4.0; and0<f6/f4<4.0.

According to still another aspect of the present disclosure, an imagecapturing device includes the optical lens according to theaforementioned aspect and an image sensor, wherein the image sensor isdisposed on an image surface of the optical lens.

According to further another aspect of the present disclosure, anelectronic device includes the image capturing device according to theaforementioned aspect.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of an image capturing device according to the1st embodiment of the present disclosure;

FIG. 2 shows spherical aberration curves, astigmatic field curves and adistortion curve of the image capturing device according to the 1stembodiment;

FIG. 3 is a schematic view of an image capturing device according to the2nd embodiment of the present disclosure;

FIG. 4 shows spherical aberration curves, astigmatic field curves and adistortion curve of the image capturing device according to the 2ndembodiment;

FIG. 5 is a schematic view of an image capturing device according to the3rd embodiment of the present disclosure;

FIG. 6 shows spherical aberration curves, astigmatic field curves and adistortion curve of the image capturing device according to the 3rdembodiment;

FIG. 7 is a schematic view of an image capturing device according to the4th embodiment of the present disclosure;

FIG. 8 shows spherical aberration curves, astigmatic field curves and adistortion curve of the image capturing device according to the 4thembodiment;

FIG. 9 is a schematic view of an image capturing device according to the5th embodiment of the present disclosure;

FIG. 10 shows spherical aberration curves, astigmatic field curves and adistortion curve of the image capturing device according to the 5thembodiment;

FIG. 11 is a schematic view of an image capturing device according tothe 6th embodiment of the present disclosure;

FIG. 12 shows spherical aberration curves, astigmatic field curves and adistortion curve of the image capturing device according to the 6thembodiment;

FIG. 13 is a schematic view of an image capturing device according tothe 7th embodiment of the present disclosure;

FIG. 14 shows spherical aberration curves, astigmatic field curves and adistortion curve of the image capturing device according to the 7thembodiment;

FIG. 15 shows a schematic view of the parameter Sag52 according to the1st embodiment of FIG. 1;

FIG. 16 is a schematic view of an electronic device according to the 8thembodiment of the present disclosure;

FIG. 17 is a schematic view of an electronic device according to the 9thembodiment of the present disclosure; and

FIG. 18 is a schematic view of an electronic device 30 according to the10th embodiment of the present disclosure.

DETAILED DESCRIPTION

An optical lens includes, in order from an object side to an image side,a first lens element, a second lens element, a third lens element, afourth lens element, a fifth lens element and a sixth lens element,wherein the optical lens has a total of six lens elements withrefractive power.

There is an air space between every two lens elements of the first lenselement, the second lens element, the third lens element, the fourthlens element, the fifth lens element and the sixth lens element that areadjacent to each other. That is, each of the first through sixth lenselements is a single and non-cemented lens element, and every two lenselements adjacent to each other are not cemented. Moreover, themanufacturing process of the cemented lenses is more complex than thenon-cemented lenses. In other words, of the first lens element, thesecond lens element, the third lens element, the fourth lens element,the fifth lens element and the sixth lens element of the optical lens,there is a space in a paraxial region between every pair of lenselements that are adjacent to each other. In particular, a secondsurface of one lens element and a first surface of the following lenselement need to have accurate curvature to ensure these two lenselements will be highly cemented. However, during the cementing process,those two lens elements might not be highly cemented due to displacementand it is thereby not favorable for the image quality of the opticallens. Therefore, according to the optical lens of the presentdisclosure, an air space in a paraxial region between every two of thefirst lens element, the second lens element, the third lens element, thefourth lens element, the fifth lens element and the sixth lens elementthat are adjacent to each other of the present disclosure improves theproblem generated by the cemented lens elements.

The first lens element with negative refractive power has an image-sidesurface being concave in a paraxial region thereof. Therefore, the fieldof view can be increased effectively so as to enlarge the range capturedby the optical lens.

The second lens element can have positive refractive power, and can havean object-side surface being convex in a paraxial region thereof and animage-side surface being concave in a paraxial region thereof.Therefore, the astigmatism of the optical lens can be corrected forenhancing the image quality, and the total track length of the opticallens can be reduced.

The third lens element can have positive refractive power, so that thetotal track length of the optical lens can be further reduced so as tomaintain the compact size thereof.

The fourth lens element with positive refractive power can have anobject-side surface being convex in a paraxial region thereof andincluding at least one concave shape in an off-axis region thereof, andhas an image-side surface being convex in a paraxial region thereof.Therefore, the sensitivity of refractive power distribution of theoptical lens can be reduced, and the incident angle of the off-axisfield onto the image sensor can be reduced so as to increase theresponse efficiency of the image sensor.

The fifth lens element with negative refractive power has an image-sidesurface being concave in a paraxial region thereof, wherein theimage-side surface of the fifth lens element can include at least oneconvex shape in an off-axis region thereof. Therefore, the aberration ina paraxial region and an off-axis region of the optical lens can becorrected for enhancing the image quality.

The sixth lens element can have positive refractive power and anobject-side surface being convex in a paraxial region thereof, and hasan image-side surface being concave in a paraxial region thereof andincluding at least one convex shape in an off-axis region thereof.Therefore, the principal point can be positioned away from the imagesurface of the optical lens so as to reduce the back focal length forkeeping a compact size. Further, it is also favorable for correcting theaberration of the off-axis region so as to enhance the image quality.

When a focal length of the first lens element is f1, and a focal lengthof the second lens element is f2, the following condition is satisfied:−1.50<|f1|/f2<4.0. Therefore, it is favorable for reducing thesensitivity of the surface accuracy of the first lens element and thesecond lens element by properly adjusting the distribution of therefractive power of the first lens element and the second lens element,and it is also favorable for manufacturing the optical lens by enlargingthe field of view. Preferably, the following condition can be satisfied:−0.70<|f1|/f2<1.80. More preferably, the following condition can besatisfied: −0.20<|f1|/f2<1.50. Further preferably, the followingcondition can be satisfied: −0.20<|f1|/f2<1.0.

When an axial distance between the first lens element and the secondlens element is T12, and an axial distance between the second lenselement and the third lens element is T23, the following condition issatisfied: 1.0<T12/T23. Therefore, the sufficient space between thefirst lens element and the second lens element can be provided so as toavoid the collision between the first lens element and the second lenselement or the second lens element and the third lens element duringassembling, and the wide field of view and compact size of the opticallens can be also achieved while providing high image quality thereof.Preferably, the following condition can be satisfied: 1.40<T12/T23.

When a focal length of the fourth lens element is f4, and a focal lengthof the sixth lens element is f6, the following condition is satisfied:0<f6/f4<4.0. Therefore, the total track length of the optical lens canbe reduced so as to maintain the compact size thereof.

When half of the maximal field of view of the optical lens is HFOV, andan axial distance between an object-side surface of the first lenselement and the image surface is TL, the following conditions aresatisfied: 1.30<tan(HFOV); and TL/sin(HFOV×1.6)<7.0 mm. Therefore, thecharacteristics of large field of view and short total track length ofthe optical lens can be provided so as to maintain the compact sizethereof.

When the axial distance between the first lens element and the secondlens element is T12, an axial distance between the third lens elementand the fourth lens element is T34, an axial distance between the fourthlens element and the fifth lens element is T45, and an axial distancebetween the fifth lens element and the sixth lens element is T56, thefollowing condition is satisfied: 1.25<T12/(T34+T45+T56)<4.0. Therefore,the lens elements between the stop and the image surface can be arrangedclosely, and the additional element, such as a spacer which is disposedbetween two lens elements with excessive distance can be omitted.

When a central thickness of the first lens element is CT1, a centralthickness of the second lens element is CT2, a central thickness of thethird lens element is CT3, a central thickness of the fourth lenselement is CT4, and a central thickness of the sixth lens element isCT6, the following conditions are satisfied: CT1<CT2; CT1<CT3; CT1<CT4;and CT1<CT6. Therefore, it is favorable for the manufacturing andassembling of the lens elements so as to obtain the high image quality.

When a focal length of the optical lens is f, and a curvature radius ofthe object-side surface of the sixth lens element is R11, the followingcondition is to satisfied: 0<R11/f<1.40. Therefore, it is favorable forobtaining high image quality by correcting the aberration generated fromthe fifth lens element. Preferably, the following condition can besatisfied: 0<R11/f<1.0.

When a central thickness of the fifth lens element is CT5, and adistance in parallel with an optical axis from an axial vertex on theimage-side surface of the fifth lens element to a maximum effectivediameter position on the image-side surface of the fifth lens element isSag52 (Sag52 is a positive value with the distance in parallel with theoptical axis towards the image side; Sag52 is a negative value with thedistance in parallel with the optical axis towards the object side), andthe following condition is satisfied: 4.0<CT5/|Sag52|. Therefore, theshape of the lens element is proper for manufacturing and formingthereof, and the defective forming can be reduced.

When a refractive index of the first lens element is N1, a refractiveindex of the second lens element is N2, a refractive index of the thirdlens element is N3, a refractive index of the fourth lens element is N4,a refractive index of the fifth lens element is N5, a refractive indexof the sixth lens element is N6, and a maximum of N1, N2, N3, N4, N5 andN6 is Nmax, the following condition is satisfied: 1.60<Nmax<1.70.Therefore, it is favorable for reducing the aberration by the propermaterial of the lens elements.

When the focal length of the first lens element is f1, the focal lengthof the second lens element is f2, a focal length of the third lenselement is f3, the focal length of the fourth lens element is f4, afocal length of the fifth lens element is f5, and the focal length ofthe sixth lens element is f6, the following conditions are satisfied:|f5|<|f1|; |f5|<|f2|; |f5|<|f3|; |f5|<|f4|; and |f5|<|f6|. Therefore, itis favorable for correcting the aberration by the proper distribution ofthe refractive power of the optical lens.

According to the optical lens of the present disclosure, the lenselements thereof can be made of glass or plastic material. When the lenselements are made of glass material, the distribution of the refractivepowers of the optical lens may be more flexible to design. When the lenselements are made of plastic material, the manufacturing cost can beeffectively reduced. Furthermore, surfaces of each lens element can bearranged to be aspheric, since the aspheric surface of the lens elementis easy to form a shape other than spherical surface so as to have morecontrollable variables for eliminating the aberration thereof, and tofurther decrease the required number of the lens elements. Therefore,the total track length of the optical lens can also be reduced.

According to the optical lens of the present disclosure, each of anobject-side surface and an image-side surface has a paraxial region andan off-axis region. The paraxial region refers to the region of thesurface where light rays travel close to the optical axis, and theoff-axis region refers to the region of the surface away from theparaxial region. Particularly, when the lens element has a convexsurface, it indicates that the surface is convex in the paraxial regionthereof; when the lens element has a concave surface, it indicates thatthe surface is concave in the paraxial region thereof.

According to the optical lens of the present disclosure, the positiverefractive power or the negative refractive power of a lens element orthe focal length of the lens element, that is, refers to the refractivepower or the focal length in a paraxial region of the lens element.

According to the optical lens of the present disclosure, the opticallens can include at least one stop, such as an aperture stop, a glarestop or a field stop. Said glare stop or said field stop is foreliminating the stray light and thereby improving the image resolutionthereof.

According to the optical lens of the present disclosure, an imagesurface of the optical lens, based on the corresponding image sensor,can be flat or curved. In particular, the image surface can be a curvedsurface being concave facing towards the object side.

According to the optical lens of the present disclosure, an aperturestop can be configured as a front stop or a middle stop. A front stopdisposed between an object and the first lens element can provide alonger distance between an exit pupil of the optical lens and the imagesurface and thereby improves the image-sensing efficiency of an imagesensor. A middle stop disposed between the first lens element and theimage surface is favorable for enlarging the field of view of theoptical lens and thereby provides a wider field of view for the same.

According to the optical lens of the present disclosure, the opticallens can be applied to 3D (three-dimensional) image capturingapplications, in products such as digital cameras, mobile devices,digital tablets, smart TV, internet monitoring device, motion sensinginput device, vehicle device (such as driving recording systems, vehiclereversing displays), rear view camera systems, and wearable devices.

According to the present disclosure, an image capturing device isprovided. The image capturing device includes the aforementioned opticallens and an image sensor, wherein the image sensor is disposed on theimage side of the aforementioned optical lens, that is, the image sensorcan be disposed on or near an image surface of the aforementionedoptical lens. In the image capturing device with the arrangement of theaforementioned optical lens, the wide field of view and the compact sizethereof can be obtained with the proper distribution of the aberrationand relative illumination, and the proper arrangement of the shape ofthe lens element can be obtained easily. Preferably, the image capturingdevice can further include a barrel member, a holding member or acombination thereof.

According to the present disclosure, an electronic device is provided.The electronic device includes the aforementioned image capturingdevice. Therefore, the image quality of the electronic device can beincreased. Preferably, the electronic device can further include but notlimited to a control unit, a display, a storage unit, a random accessmemory unit (RAM), a read only memory unit (ROM) or a combinationthereof.

According to the above description of the present disclosure, thefollowing 1st-10th specific embodiments are provided for furtherexplanation.

1st Embodiment

FIG. 1 is a schematic view of an image capturing device according to the1st embodiment of the present disclosure. FIG. 2 shows sphericalaberration curves, astigmatic field curves and a distortion curve of theimage capturing device according to the 1st embodiment. In FIG. 1, theimage capturing device includes an optical lens (its reference numeralis omitted) and an image sensor 190. The optical lens includes, in orderfrom an object side to an image side, a first lens element 110, a secondlens element 120, an aperture stop 100, a third lens element 130, afourth lens element 140, a fifth lens element 150, a sixth lens element160, an IR-cut filter 170 and an image surface 180, wherein the imagesensor 190 is disposed on the image surface 180 of the optical lens. Theoptical lens has a total of sixth lens elements (110-160) withrefractive power, and there is an air space between every two lenselements of the first lens element 110, the second lens element 120, thethird lens element 130, the fourth lens element 140, the fifth lenselement 150 and the sixth lens element 160 that are adjacent to eachother.

The first lens element 110 with negative refractive power has anobject-side surface 111 being convex in a paraxial region thereof and animage-side surface 112 being concave in a paraxial region thereof. Thefirst lens element 110 is made of plastic material, and has theobject-side surface 111 and the image-side surface 112 being bothaspheric.

The second lens element 120 with negative refractive power has anobject-side surface 121 being convex in a paraxial region thereof and animage-side surface 122 being concave in a paraxial region thereof. Thesecond lens element 120 is made of plastic material, and has theobject-side surface 121 and the image-side surface 122 being bothaspheric.

The third lens element 130 with positive refractive power has anobject-side surface 131 being convex in a paraxial region thereof and animage-side surface 132 being convex in a paraxial region thereof. Thethird lens element 130 is made of plastic material, and has theobject-side surface 131 and the image-side surface 132 being bothaspheric.

The fourth lens element 140 with positive refractive power has anobject-side surface 141 being convex in a paraxial region thereof, andan image-side surface 142 being convex in a paraxial region thereof andincluding at least one concave shape in an off-axis region thereof. Thefourth lens element 140 is made of plastic material, and has theobject-side surface 141 and the image-side surface 142 being bothaspheric.

The fifth lens element 150 with negative refractive power has anobject-side surface 151 being concave in a paraxial region thereof, andan image-side surface 152 being concave in a paraxial region thereof andincluding at least one convex shape in an off-axis region thereof. Thefifth lens element 150 is made of plastic material, and has theobject-side surface 151 and the image-side surface 152 being bothaspheric.

The sixth lens element 160 with positive refractive power has anobject-side surface 161 being convex in a paraxial region thereof, andan image-side surface 162 being concave in a paraxial region thereof andincluding at least one convex shape in an off-axis region thereof. Thesixth lens element 160 is made of plastic material, and has theobject-side surface 161 and the image-side surface 162 being bothaspheric.

The IR-cut filter 170 is made of glass material and located between thesixth lens element 160 and the image surface 180, and will not affect afocal length of the optical lens.

The equation of the aspheric surface profiles of the aforementioned lenselements of the 1st embodiment is expressed as follows:

${{X(Y)} = {{\left( {Y^{2}/R} \right)/\left( {1 + {{sqrt}\left( {1 - {\left( {1 + k} \right) \times \left( {Y/R} \right)^{2}}} \right)}} \right)} + {\sum\limits_{i}\;{({Ai}) \times \left( Y^{i} \right)}}}},$where,

X is the relative distance between a point on the aspheric surfacespaced at a distance Y from the optical axis and the tangential plane atthe aspheric surface vertex on the optical axis;

Y is the vertical distance from the point on the aspheric surface to theoptical axis;

R is the curvature radius;

k is the conic coefficient; and

Ai is the i-th aspheric coefficient.

In the optical lens according to the 1st embodiment, when a focal lengthof the optical lens is f, an f-number of the optical lens is Fno, andhalf of a maximal field of view of the optical lens is HFOV, theseparameters have the following values: f=1.00 mm; Fno=2.15; and HFOV=63.5degrees.

In the optical lens according to the 1st embodiment, when half of themaximal field of view of the optical lens is HFOV, the followingcondition is satisfied: tan(HFOV)=2.01.

In the optical lens according to the 1st embodiment, when a refractiveindex of the first lens element 110 is N1, a refractive index of thesecond lens element 120 is N2, a refractive index of the third lenselement 130 is N3, a refractive index of the fourth lens element 140 isN4, a refractive index of the fifth lens element 150 is N5, a refractiveindex of the sixth lens element 160 is N6, and a maximum of N1, N2, N3,N4, N5 and N6 is Nmax, the following condition is satisfied: Nmax=1.633.

In the optical lens according to the 1st embodiment, when an axialdistance between the first lens element 110 and the second lens element120 is T12, an axial distance between the second lens element 120 andthe third lens element 130 is T23, an axial distance between the thirdlens element 130 and the fourth lens element 140 is T34, an axialdistance between the fourth lens element 140 and the fifth lens element150 is T45, and an axial distance between the fifth lens element 150 andthe sixth lens element 160 is T56, the following conditions aresatisfied: T12/T23=1.85; and T12/(T34+T45+T56)=1.51.

In the optical lens according to the 1st embodiment, when half of themaximal field of view of the optical lens is HFOV, and an axial distancebetween the object-side surface 111 of the first lens element 110 andthe image surface 180 is TL, the following condition is satisfied:TL/sin(HFOV×1.6)=4.30 mm.

FIG. 15 shows a schematic view of the parameter Sag52 according to the1st embodiment of FIG. 1. In FIG. 15, when a distance in parallel withan optical axis from an axial vertex on the image-side surface 152 ofthe fifth lens element 150 to a maximum effective diameter position onthe image-side surface 152 of the fifth lens element 150 is Sag52, and acentral thickness of the fifth lens element 150 is CT5, the followingcondition is satisfied: CT5/|Sag52|=7.18.

In the optical lens according to the 1st embodiment, when the focallength of the optical lens is f, and a curvature radius of theobject-side surface 161 of the sixth lens element 160 is R11, thefollowing condition is satisfied: R11/f=0.56.

In the optical lens according to the 1st embodiment, when a focal lengthof the first lens element 110 is f1, and a focal length of the secondlens element 120 is f2, the following condition is satisfied:|f1|/f2=−0.04.

In the optical lens according to the 1st embodiment, when a focal lengthof the fourth lens element 140 is f4, and a focal length of the sixthlens element 160 is f6, the following condition is satisfied:f6/f4=1.06.

In the optical lens according to the 1st embodiment, when a centralthickness of the first lens element 110 is CT1, a central thickness ofthe second lens element 120 is CT2, a central thickness of the thirdlens element 130 is CT3, a central thickness of the fourth lens element140 is CT4, and a central thickness of the sixth lens element 160 isCT6, the following conditions are satisfied: CT1<CT2; CT1<CT3; CT1<CT4;and CT1<CT6.

In the optical lens according to the 1st embodiment, when the focallength of the first lens element 110 is f1, the focal length of thesecond lens element 120 is f2, a focal length of the third lens element130 is f3, the focal length of the fourth lens element 140 is f4, afocal length of the fifth lens element 150 is f5, and the focal lengthof the sixth lens element 160 is f, the following conditions aresatisfied: |f5|<|f1|; |f5|<|f2|; |f5|<|f3|; |f5|<|f4|; and |f5|<|f6|.

The detailed optical data of the 1st embodiment are shown in Table 1 andthe aspheric surface data are shown in Table 2 below.

TABLE 1 1st Embodiment f = 1.00 mm, Fno = 2.15, HFOV = 63.5 deg.Curvature Focal Surface # Radius Thickness Material Index Abbe # Length0 Object Plano Infinity 1 Lens 1 2.018 ASP 0.255 Plastic 1.544 55.9−1.49 2 0.553 ASP 0.425 3 Lens 2 0.995 ASP 0.300 Plastic 1.633 23.4−33.50 4 0.840 ASP 0.256 5 Ape. Stop Plano −0.026 6 Lens 3 2.263 ASP0.472 Plastic 1.514 56.8 1.59 7 −1.188 ASP 0.104 8 Lens 4 2.440 ASP0.640 Plastic 1.644 55.9 0.98 9 −0.623 ASP 0.095 10 Lens 5 −0.645 ASP0.255 Plastic 1.633 23.4 −0.62 11 1.166 ASP 0.082 12 Lens 6 0.564 ASP0.636 Plastic 1.544 55.9 1.04 13 83.034 ASP 0.400 14 IR-cut filter Plano0.110 Glass 1.517 64.2 — 15 Plano 0.205 16 Image Plano — Note: Referencewavelength is 587.6 nm (d-line).

TABLE 2 Aspheric Coefficients Surface # 1 2 3 4 6 7 k = −4.9227E−02−7.3854E−01 2.4401E−01 −2.6108E+00 8.8144E+00 −3.0299E+00 A4 =3.1658E−01 4.4670E−01 −1.1812E−02 1.5348E+00 2.4989E−02 −1.2630E+00 A6 =−8.1019E−01 −2.2742E−01 1.2351E+00 4.4101E+00 −5.5532E−01 2.0216E+00 A8= 7.8938E−01 −1.1679E+01 −1.6029E+01 −4.4695E+01 6.8535E+00 −1.0459E+01A10 = −3.5874E−01 2.8169E+01 5.9385E+01 4.7020E+02 −1.9666E+012.0715E+01 A12 = 6.3971E−02 −1.8875E+01 −7.2674E+01 −9.6417E+02 Surface# 8 9 10 11 12 13 k = 3.9565E−01 −8.9787E−01 −8.4168E−01 −3.6612E+01−6.5044E+00 3.0359E+01 A4 = −5.3590E−01 2.7958E+00 3.7728E+00−8.3013E−02 −7.6512E−02 3.6772E−01 A6 = 7.9918E−01 −1.6443E+01−2.4033E+01 −3.6156E−01 2.9110E−01 −4.8043E−01 A8 = −1.4788E+004.8331E+01 7.6076E+01 7.2435E−01 −7.4546E−01 2.2581E−01 A10 =−3.2925E+00 −7.5388E+01 −1.5158E+02 −6.6294E−01 7.8278E−01 −4.5073E−02A12 = 4.7744E+01 1.7735E+02 3.9845E−01 −3.8651E−01 2.1856E−02 A14 =−8.7128E+01 −1.1724E−01 7.3004E−02 −1.6020E−02 A16 = 3.3656E−03

In Table 1, the curvature radius, the thickness and the focal length areshown in millimeters (mm). Surface numbers 0-16 represent the surfacessequentially arranged from the object-side to the image-side along theoptical axis. In Table 2, k represents the conic coefficient of theequation of the aspheric surface profiles. A4-A16 represent the asphericcoefficients ranging from the 4th order to the 16th order. The tablespresented below for each embodiment are the corresponding schematicparameter and aberration curves, and the definitions of the tables arethe same as Table 1 and Table 2 of the 1st embodiment. Therefore, anexplanation in this regard will not be provided again.

2nd Embodiment

FIG. 3 is a schematic view of an image capturing device according to the2nd embodiment of the present disclosure. FIG. 4 shows sphericalaberration curves, astigmatic field curves and a distortion curve of theimage capturing device according to the 2nd embodiment. In FIG. 3, theimage capturing device includes an optical lens (its reference numeralis omitted) and an image sensor 290. The optical lens includes, in orderfrom an object side to an image side, a first lens element 210, a secondlens element 220, an aperture stop 200, a third lens element 230, afourth lens element 240, a fifth lens element 250, a sixth lens element260, an IR-cut filter 270 and an image surface 280, wherein the imagesensor 290 is disposed on the image surface 280 of the optical lens. Theoptical lens has a total of sixth lens elements (210-260) withrefractive power, and there is an air space between every two lenselements of the first lens element 210, the second lens element 220, thethird lens element 230, the fourth lens element 240, the fifth lenselement 250 and the sixth lens element 260 that are adjacent to eachother.

The first lens element 210 with negative refractive power has anobject-side surface 211 being convex in a paraxial region thereof and animage-side surface 212 being concave in a paraxial region thereof. Thefirst lens element 210 is made of plastic material, and has theobject-side surface 211 and the image-side surface 212 being bothaspheric.

The second lens element 220 with positive refractive power has anobject-side surface 221 being convex in a paraxial region thereof and animage-side surface 222 being concave in a paraxial region thereof. Thesecond lens element 220 is made of plastic material, and has theobject-side surface 221 and the image-side surface 222 being bothaspheric.

The third lens element 230 with positive refractive power has anobject-side surface 231 being convex in a paraxial region thereof and animage-side surface 232 being convex in a paraxial region thereof. Thethird lens element 230 is made of plastic material, and has theobject-side surface 231 and the image-side surface 232 being bothaspheric.

The fourth lens element 240 with positive refractive power has anobject-side surface 241 being concave in a paraxial region thereof, andan image-side surface 242 being convex in a paraxial region thereof andincluding at least one concave shape in an off-axis region thereof. Thefourth lens element 240 is made of plastic material, and has theobject-side surface 241 and the image-side surface 242 being bothaspheric.

The fifth lens element 250 with negative refractive power has anobject-side surface 251 being concave in a paraxial region thereof, andan image-side surface 252 being concave in a paraxial region thereof andincluding at least one convex shape in an off-axis region thereof. Thefifth lens element 250 is made of plastic material, and has theobject-side surface 251 and the image-side surface 252 being bothaspheric.

The sixth lens element 260 with positive refractive power has anobject-side surface 261 being convex in a paraxial region thereof, andan image-side surface 262 being concave in a paraxial region thereof andincluding at least one convex shape in an off-axis region thereof. Thesixth lens element 260 is made of plastic material, and has theobject-side surface 261 and the image-side surface 262 being bothaspheric.

The IR-cut filter 270 is made of glass material and located between thesixth lens element 260 and the image surface 280, and will not affect afocal length of the optical lens.

The detailed optical data of the 2nd embodiment are shown in Table 3 andthe aspheric surface data are shown in Table 4 below.

TABLE 3 2nd Embodiment f = 1.23 mm, Fno = 2.38, HFOV = 59.5 deg.Curvature Focal Surface # Radius Thickness Material Index Abbe # Length0 Object Plano Infinity 1 Lens 1 2.156 ASP 0.316 Plastic 1.544 55.9−1.77 2 0.632 ASP 0.487 3 Lens 2 1.073 ASP 0.403 Plastic 1.645 22.518.26 4 1.007 ASP 0.271 5 Ape. Stop Plano −0.008 6 Lens 3 4.609 ASP0.495 Plastic 1.535 55.7 1.49 7 −0.930 ASP 0.093 8 Lens 4 −13.833 ASP0.697 Plastic 1.535 55.7 2.10 9 −1.059 ASP 0.076 10 Lens 5 −1.344 ASP0.270 Plastic 1.645 22.5 −1.01 11 1.351 ASP 0.040 12 Lens 6 0.638 ASP0.800 Plastic 1.544 55.9 1.22 13 8.813 ASP 0.419 14 IR-cut filter Plano0.210 Glass 1.517 64.2 — 15 Plano 0.285 16 Image Plano — Note: Referencewavelength is 587.6 nm (d-line).

TABLE 4 Aspheric Coefficients Surface # 1 2 3 4 6 7 k = −6.2694E−02−7.7175E−01 1.0203E−01 −1.8197E+00 7.3347E+01 −5.9589E+00 A4 =1.7715E−01 3.7902E−01 −4.4158E−02 1.0408E+00 4.4296E−01 −9.4897E−01 A6 =−3.2289E−01 −8.7987E−01 1.4120E+00 −1.4223E+00 −1.5785E+01 7.7901E+00 A8= 2.2767E−01 9.4688E−01 −8.3321E+00 1.0142E+02 3.7328E+02 −9.8073E+01A10 = −8.9832E−02 −5.3241E+00 2.7021E+01 −1.2939E+03 −4.9099E+037.0348E+02 A12 = 2.3859E−02 1.2348E+01 −5.1534E+01 9.2029E+03 3.6855E+04−2.8651E+03 A14 = −4.9108E−03 −1.1195E+01 5.8472E+01 −3.0881E+04−1.4520E+05 6.1838E+03 A16 = 6.0765E−04 3.5230E+00 −3.5683E+014.0081E+04 2.3223E+05 −5.3510E+03 Surface # 8 9 10 11 12 13 k =9.0000E+01 −2.1221E−01 9.2211E−01 −4.2143E+01 −8.2127E+00 −4.4046E+00 A4= 4.6803E−01 3.7134E−01 4.2203E−01 −7.3321E−01 6.8748E−02 6.6934E−01 A6= −2.1324E+00 −1.1087E+00 −3.6910E−01 2.8509E+00 −9.1382E−01 −1.6533E+00A8 = 6.2700E+00 −3.4985E+00 −4.5836E+00 −5.6666E+00 2.2292E+001.9444E+00 A10 = −1.3252E+01 1.9532E+01 9.2953E+00 5.8564E+00−2.5713E+00 −1.3127E+00 A12 = 2.1989E+00 −3.7505E+01 −7.6654E+00−3.0255E+00 1.4212E+00 5.0231E−01 A14 = 3.5065E+01 3.2860E+01 6.7683E+005.6856E−01 −3.0842E−01 −1.0074E−01 A16 = −3.8438E+01 −1.0169E+01−3.7196E+00 3.4356E−02 8.2114E−03

In the 2nd embodiment, the equation of the aspheric surface profiles ofthe aforementioned lens elements is the same as the equation of the 1stembodiment. Also, the definitions of these parameters shown in thefollowing table are the same as those stated in the 1st embodiment withcorresponding values for the 2nd embodiment, so an explanation in thisregard will not be provided again.

Moreover, these parameters can be calculated from Table 3 and Table 4 asthe following values and satisfy the following conditions:

2nd Embodiment f [mm] 1.23 T12/(T34 + T45 + T56) 2.33 Fno 2.38TL/sin(HFOV × 1.6) [mm] 4.87 HFOV [deg.] 59.5 CT5/|Sag52| 48.68tan(HFOV) 1.70 R11/f 0.52 Nmax 1.645 |f1|/f2 0.10 T12/T23 1.85 f6/f40.58

Furthermore, according to the 2nd embodiment, when a central thicknessof the first lens element 210 is CT1, a central thickness of the secondlens element 220 is CT2, a central thickness of the third lens element230 is CT3, a central thickness of the fourth lens element 240 is CT4,and a central thickness of the sixth lens element 260 is CT6, thefollowing conditions are satisfied: CT1<CT2; CT1<CT3; CT1<CT4; andCT1<CT6.

According to the 2nd embodiment, when the focal length of the first lenselement 210 is f1, the focal length of the second lens element 220 isf2, a focal length of the third lens element 230 is f3, the focal lengthof the fourth lens element 240 is f4, a focal length of the fifth lenselement 250 is f5, and the focal length of the sixth lens element 260 isf6, the following conditions are satisfied: |f5|<|f1|; |f5|<|f2|;|f5|<|f3|; |f5|<|f4|; and |f5|<|f6|.

3rd Embodiment

FIG. 5 is a schematic view of an image capturing device according to the3rd embodiment of the present disclosure. FIG. 6 shows sphericalaberration curves, astigmatic field curves and a distortion curve of theimage capturing device according to the 3rd embodiment. In FIG. 5, theimage capturing device includes an optical lens (its reference numeralis omitted) and an image sensor 390. The optical lens includes, in orderfrom an object side to an image side, a first lens element 310, a secondlens element 320, an aperture stop 300, a third lens element 330, afourth lens element 340, a fifth lens element 350, a sixth lens element360, an IR-cut filter 370 and an image surface 280, wherein the imagesensor 290 is disposed on the image surface 380 of the optical lens. Theoptical lens has a total of sixth lens elements (310-360) withrefractive power, and there is an air space between every two lenselements of the first lens element 310, the second lens element 320, thethird lens element 330, the fourth lens element 340, the fifth lenselement 350 and the sixth lens element 360 that are adjacent to eachother.

The first lens element 310 with negative refractive power has anobject-side surface 311 being convex in a paraxial region thereof and animage-side surface 312 being concave in a paraxial region thereof. Thefirst lens element 310 is made of plastic material, and has theobject-side surface 311 and the image-side surface 312 being bothaspheric.

The second lens element 320 with positive refractive power has anobject-side surface 321 being convex in a paraxial region thereof and animage-side surface 322 being concave in a paraxial region thereof. Thesecond lens element 320 is made of plastic material, and has theobject-side surface 321 and the image-side surface 322 being bothaspheric.

The third lens element 330 with positive refractive power has anobject-side surface 331 being convex in a paraxial region thereof and animage-side surface 332 being convex in a paraxial region thereof. Thethird lens element 330 is made of plastic material, and has theobject-side surface 331 and the image-side surface 332 being bothaspheric.

The fourth lens element 340 with positive refractive power has anobject-side surface 341 being convex in a paraxial region thereof, andan image-side surface 342 being convex in a paraxial region thereof andincluding at least one concave shape in an off-axis region thereof. Thefourth lens element 340 is made of plastic material, and has theobject-side surface 341 and the image-side surface 342 being bothaspheric.

The fifth lens element 350 with negative refractive power has anobject-side surface 351 being concave in a paraxial region thereof, andan image-side surface 352 being concave in a paraxial region thereof andincluding at least one convex shape in an off-axis region thereof. Thefifth lens element 350 is made of plastic material, and has theobject-side surface 351 and the image-side surface 352 being bothaspheric.

The sixth lens element 360 with positive refractive power has anobject-side surface 361 being convex in a paraxial region thereof, andan image-side surface 362 being concave in a paraxial region thereof andincluding at least one convex shape in an off-axis region thereof. Thesixth lens element 360 is made of plastic material, and has theobject-side surface 361 and the image-side surface 362 being bothaspheric.

The IR-cut filter 370 is made of glass material and located between thesixth lens element 360 and the image surface 380, and will not affect afocal length of the optical lens.

The detailed optical data of the 3rd embodiment are shown in Table 5 andthe aspheric surface data are shown in Table 6 below.

TABLE 5 3rd Embodiment f = 1.22 mm, Fno = 2.29, HFOV = 59.3 deg.Curvature Focal Surface # Radius Thickness Material Index Abbe # Length0 Object Plano Infinity 1 Lens 1 2.000 ASP 0.240 Plastic 1.544 55.9−1.77 2 0.623 ASP 0.558 3 Lens 2 1.234 ASP 0.401 Plastic 1.639 23.5 6.344 1.550 ASP 0.214 5 Ape. Stop Plano −0.052 6 Lens 3 1.457 ASP 0.359Plastic 1.544 55.9 2.18 7 −5.780 ASP 0.037 8 Lens 4 4.765 ASP 0.532Plastic 1.544 55.9 1.05 9 −0.624 ASP 0.052 10 Lens 5 −1.116 ASP 0.260Plastic 1.639 23.5 −1.01 11 1.678 ASP 0.122 12 Lens 6 0.694 ASP 0.493Plastic 1.544 55.9 2.31 13 1.161 ASP 0.400 14 IR-cut filter Plano 0.110Glass 1.517 64.2 — 15 Plano 0.266 16 Image Plano — Note: Referencewavelength is 587.6 nm (d-line). An effective radius of surface 9 is0.602 mm.

TABLE 6 Aspheric Coefficients Surface # 1 2 3 4 6 7 k = 6.6510E−01−7.4191E−01 1.5808E−01 −4.9821E+01 −4.1944E+01 7.7108E+01 A4 =4.9732E−02 3.1281E−02 −2.9219E−01 2.1238E+00 1.7435E+00 −1.5372E+00 A6 =−1.4418E−01 −3.0106E−01 −6.9012E−02 −1.4986E+01 −7.8759E+00 4.1014E−02A8 = 1.2291E−01 −5.5456E−01 −8.8010E−01 1.3307E+02 2.9283E+01−1.7734E+01 A10 = −4.9994E−02 6.6756E−01 3.8858E+00 −5.9453E+02−3.1698E+01 1.0875E+02 A12 = 6.9888E−03 −1.4797E−01 −3.4025E+001.2908E+03 −1.5926E+02 −2.4371E+02 Surface # 8 9 10 11 12 13 k =−2.0230E+01 −1.0363E+00 2.7882E−01 −8.9105E+01 −7.6251E+00 −4.9220E−01A4 = −1.4020E+00 3.3735E+00 3.3679E+00 2.4872E−01 −2.2356E−01−5.8941E−01 A6 = 1.3879E−01 −3.2539E+01 −3.0602E+01 −2.2698E+001.8790E−01 4.7706E−01 A8 = −1.9381E+01 1.4231E+02 1.1570E+02 5.6244E+003.0428E−02 −3.3868E−01 A10 = 4.2267E+01 −3.3557E+02 −2.5375E+02−7.8399E+00 −2.2646E−01 1.5986E−01 A12 = 3.4845E+02 2.6826E+025.8524E+00 1.5386E−01 −5.1300E−02 A14 = −6.0171E+01 −1.7946E+00−3.1275E−02 7.5929E−03

In the 3rd embodiment, the equation of the aspheric surface profiles ofthe aforementioned lens elements is the same as the equation of the 1stembodiment. Also, the definitions of these parameters shown in thefollowing table are the same as those stated in the 1st embodiment withcorresponding values for the 3rd embodiment, so an explanation in thisregard will not be provided again.

Moreover, these parameters can be calculated from Table 5 and Table 6 asthe following values and satisfy the following conditions:

3rd Embodiment f [mm] 1.22 T12/(T34 + T45 + T56) 2.64 Fno 2.29TL/sin(HFOV × 1.6) [mm] 4.01 HFOV [deg.] 59.3 CT5/|Sag52| 2.48 tan(HFOV)1.68 R11/f 0.57 Nmax 1.639 |f1|/f2 0.28 T12/T23 3.44 f6/f4 2.20

Furthermore, according to the 3rd embodiment, when a central thicknessof the first lens element 310 is CT1, a central thickness of the secondlens element 320 is CT2, a central thickness of the third lens element330 is CT3, a central thickness of the fourth lens element 340 is CT4,and a central thickness of the sixth lens element 360 is CT6, thefollowing conditions are satisfied: CT1<CT2; CT1<CT3; CT1<CT4; andCT1<CT6.

According to the 3rd embodiment, when the focal length of the first lenselement 310 is f1, the focal length of the second lens element 320 isf2, a focal length of the third lens element 330 is f3, the focal lengthof the fourth lens element 340 is f4, a focal length of the fifth lenselement 350 is f5, and the focal length of the sixth lens element 360 isf6, the following conditions are satisfied: |f5|<|f1|; |f5|<|f2|;|f5|<|f3|; |f5|<|f4|; and |f5|<|f6|.

4th Embodiment

FIG. 7 is a schematic view of an image capturing device according to the4th embodiment of the present disclosure. FIG. 8 shows sphericalaberration curves, astigmatic field curves and a distortion curve of theimage capturing device according to the 4th embodiment. In FIG. 7, theimage capturing device includes an optical lens (its reference numeralis omitted) and an image sensor 490. The optical lens includes, in orderfrom an object side to an image side, a first lens element 410, a secondlens element 420, an aperture stop 400, a third lens element 430, afourth lens element 440, a fifth lens element 450, a sixth lens element460, an IR-cut filter 470 and an image surface 480, wherein the imagesensor 490 is disposed on the image surface 480 of the optical lens. Theoptical lens has a total of sixth lens elements (410-460) withrefractive power, and there is an air space between every two lenselements of the first lens element 410, the second lens element 420, thethird lens element 430, the fourth lens element 440, the fifth lenselement 450 and the sixth lens element 460 that are adjacent to eachother.

The first lens element 410 with negative refractive power has anobject-side surface 411 being convex in a paraxial region thereof and animage-side surface 412 being concave in a paraxial region thereof. Thefirst lens element 410 is made of plastic material, and has theobject-side surface 411 and the image-side surface 412 being bothaspheric.

The second lens element 420 with positive refractive power has anobject-side surface 421 being convex in a paraxial region thereof and animage-side surface 422 being concave in a paraxial region thereof. Thesecond lens element 420 is made of plastic material, and has theobject-side surface 421 and the image-side surface 422 being bothaspheric.

The third lens element 430 with positive refractive power has anobject-side surface 431 being convex in a paraxial region thereof and animage-side surface 432 being convex in a paraxial region thereof. Thethird lens element 430 is made of plastic material, and has theobject-side surface 431 and the image-side surface 432 being bothaspheric.

The fourth lens element 440 with positive refractive power has anobject-side surface 441 being convex in a paraxial region thereof, andan image-side surface 442 being convex in a paraxial region thereof andincluding at least one concave shape in an off-axis region thereof. Thefourth lens element 440 is made of plastic material, and has theobject-side surface 441 and the image-side surface 442 being bothaspheric.

The fifth lens element 450 with negative refractive power has anobject-side surface 451 being concave in a paraxial region thereof, andan image-side surface 452 being concave in a paraxial region thereof andincluding at least one convex shape in an off-axis region thereof. Thefifth lens element 450 is made of plastic material, and has theobject-side surface 451 and the image-side surface 452 being bothaspheric.

The sixth lens element 460 with positive refractive power has anobject-side surface 461 being convex in a paraxial region thereof, andan image-side surface 462 being concave in a paraxial region thereof andincluding at least one convex shape in an off-axis region thereof. Thesixth lens element 460 is made of plastic material, and has theobject-side surface 461 and the image-side surface 462 being bothaspheric.

The IR-cut filter 470 is made of glass material and located between thesixth lens element 460 and the image surface 480, and will not affect afocal length of the optical lens.

The detailed optical data of the 4th embodiment are shown in Table 7 andthe aspheric surface data are shown in Table 8 below.

TABLE 7 4th Embodiment f = 1.21 mm, Fno = 2.29, HFOV = 62.5 deg.Curvature Focal Surface # Radius Thickness Material Index Abbe # Length0 Object Plano Infinity 1 Lens 1 2.320 ASP 0.255 Plastic 1.544 55.9−1.64 2 0.618 ASP 0.350 3 Lens 2 0.971 ASP 0.330 Plastic 1.639 23.511.15 4 0.975 ASP 0.233 5 Ape. Stop Plano −0.016 6 Lens 3 3.083 ASP0.402 Plastic 1.544 55.9 2.30 7 −2.008 ASP 0.079 8 Lens 4 1.693 ASP0.544 Plastic 1.544 55.9 1.18 9 −0.923 ASP 0.085 10 Lens 5 −1.050 ASP0.255 Plastic 1.639 23.5 −1.00 11 1.784 ASP 0.114 12 Lens 6 0.585 ASP0.602 Plastic 1.544 55.9 1.47 13 1.387 ASP 0.400 14 IR-cut filter Plano0.110 Glass 1.517 64.2 — 15 Plano 0.278 16 Image Plano — Note: Referencewavelength is 587.6 nm (d-line). An effective radius of surface 9 is0.680 mm.

TABLE 8 Aspheric Coefficients Surface # 1 2 3 4 6 7 k = 7.8130E−01−5.9483E−01 4.1545E−02 −4.2152E+00 −7.1386E+01 6.7053E+00 A4 =2.8900E−01 2.8338E−01 −1.2832E−01 1.3309E+00 2.0773E−01 −1.5676E+00 A6 =−7.8629E−01 −3.3970E−01 1.5512E+00 4.4136E+00 4.4017E−01 4.0307E+00 A8 =7.9195E−01 −1.1156E+01 −1.7799E+01 −5.1361E+01 −9.1240E+00 −1.6428E+01A10 = −3.6265E−01 2.7921E+01 6.4628E+01 4.9786E+02 3.6220E+01 2.6340E+01A12 = 6.3971E−02 −1.8875E+01 −7.2674E+01 −9.6417E+02 Surface # 8 9 10 1112 13 k = −5.9166E−01 −2.6962E−01 −4.8300E−01 −9.0000E+01 −6.0422E+00−4.9498E−01 A4 = −1.1343E+00 1.7989E+00 2.4056E+00 −3.2929E−01−1.9229E−01 −2.1528E−01 A6 = 3.5339E+00 −1.6929E+01 −2.1501E+013.3271E−01 −2.6572E−01 −2.3782E−01 A8 = −1.1338E+01 6.4067E+017.8220E+01 5.1354E−02 9.8844E−01 5.8855E−01 A10 = 1.3852E+01 −1.2192E+02−1.6934E+02 −9.8256E−01 −1.4276E+00 −6.2474E−01 A12 = 9.6765E+012.1172E+02 1.5261E+00 9.1548E−01 3.5322E−01 A14 = −1.0877E+02−6.8369E−01 −2.1057E−01 −1.0456E−01 A16 = 1.2796E−02

In the 4th embodiment, the equation of the aspheric surface profiles ofthe aforementioned lens elements is the same as the equation of the 1stembodiment. Also, the definitions of these parameters shown in thefollowing table are the same as those stated in the 1st embodiment withcorresponding values for the 4th embodiment, so an explanation in thisregard will not be provided again.

Moreover, these parameters can be calculated from Table 7 and Table 8 asthe following values and satisfy the following conditions:

4th Embodiment f [mm] 1.21 T12/(T34 + T45 + T56) 1.26 Fno 2.29TL/sin(HFOV × 1.6) [mm] 4.08 HFOV [deg.] 62.5 CT5/|Sag52| 42.10tan(HFOV) 1.92 R11/f 0.48 Nmax 1.639 |f1|/f2 0.15 T12/T23 1.61 f6/f41.25

Furthermore, according to the 4th embodiment, when a central thicknessof the first lens element 410 is CT1, a central thickness of the secondlens element 420 is CT2, a central thickness of the third lens element430 is CT3, a central thickness of the fourth lens element 440 is CT4,and a central thickness of the sixth lens element 460 is CT6, thefollowing conditions are satisfied: CT1<CT2; CT1<CT3; CT1<CT4; andCT1<CT6.

According to the 4th embodiment, when the focal length of the first lenselement 410 is f1, the focal length of the second lens element 420 isf2, a focal length of the third lens element 430 is f3, the focal lengthof the fourth lens element 440 is f4, a focal length of the fifth lenselement 450 is f5, and the focal length of the sixth lens element 460 isf6, the following conditions are satisfied: |f5|<|f1|; |f5|<|f2|;|f5|<|f3|; |f5|<|f4|; and |f5|<|f6|.

5th Embodiment

FIG. 9 is a schematic view of an image capturing device according to the5th embodiment of the present disclosure. FIG. 10 shows sphericalaberration curves, astigmatic field curves and a distortion curve of theimage capturing device according to the 5th embodiment. In FIG. 9, theimage capturing device includes an optical lens (its reference numeralis omitted) and an image sensor 590. The optical lens includes, in orderfrom an object side to an image side, a first lens element 510, a secondlens element 520, an aperture stop 500, a third lens element 530, afourth lens element 540, a fifth lens element 550, a sixth lens element560, an IR-cut filter 570 and an image surface 580, wherein the imagesensor 590 is disposed on the image surface 580 of the optical lens. Theoptical lens has a total of sixth lens elements (510-560) withrefractive power, and there is an air space between every two lenselements of the first lens element 510, the second lens element 520, thethird lens element 530, the fourth lens element 540, the fifth lenselement 550 and the sixth lens element 560 that are adjacent to eachother.

The first lens element 510 with negative refractive power has anobject-side surface 511 being convex in a paraxial region thereof and animage-side surface 512 being concave in a paraxial region thereof. Thefirst lens element 510 is made of plastic material, and has theobject-side surface 511 and the image-side surface 512 being bothaspheric.

The second lens element 520 with positive refractive power has anobject-side surface 521 being convex in a paraxial region thereof and animage-side surface 522 being concave in a paraxial region thereof. Thesecond lens element 520 is made of plastic material, and has theobject-side surface 521 and the image-side surface 522 being bothaspheric.

The third lens element 530 with positive refractive power has anobject-side surface 531 being convex in a paraxial region thereof and animage-side surface 532 being convex in a paraxial region thereof. Thethird lens element 530 is made of plastic material, and has theobject-side surface 531 and the image-side surface 532 being bothaspheric.

The fourth lens element 540 with positive refractive power has anobject-side surface 541 being convex in a paraxial region thereof, andan image-side surface 542 being convex in a paraxial region thereof andincluding at least one concave shape in an off-axis region thereof. Thefourth lens element 540 is made of plastic material, and has theobject-side surface 541 and the image-side surface 542 being bothaspheric.

The fifth lens element 550 with negative refractive power has anobject-side surface 551 being concave in a paraxial region thereof, andan image-side surface 552 being concave in a paraxial region thereof andincluding at least one convex shape in an off-axis region thereof. Thefifth lens element 550 is made of plastic material, and has theobject-side surface 551 and the image-side surface 552 being bothaspheric.

The sixth lens element 560 with positive refractive power has anobject-side surface 561 being convex in a paraxial region thereof, andan image-side surface 562 being concave in a paraxial region thereof andincluding at least one convex shape in an off-axis region thereof. Thesixth lens element 560 is made of plastic material, and has theobject-side surface 561 and the image-side surface 562 being bothaspheric.

The IR-cut filter 570 is made of glass material and located between thesixth lens element 560 and the image surface 580, and will not affect afocal length of the optical lens.

The detailed optical data of the 5th embodiment are shown in Table 9 andthe aspheric surface data are shown in Table 10 below.

TABLE 9 5th Embodiment f = 1.30 mm, Fno = 2.67, HFOV = 58.6 deg.Curvature Focal Surface # Radius Thickness Material Index Abbe # Length0 Object Plano Infinity 1 Lens 1 2.023 ASP 0.322 Plastic 1.544 55.9−1.79 2 0.620 ASP 0.487 3 Lens 2 1.073 ASP 0.401 Plastic 1.544 55.923.56 4 1.017 ASP 0.275 5 Ape. Stop Plano −0.007 6 Lens 3 3.574 ASP0.480 Plastic 1.544 55.9 1.48 7 −0.992 ASP 0.090 8 Lens 4 9.424 ASP0.689 Plastic 1.514 56.8 2.30 9 −1.317 ASP 0.070 10 Lens 5 −1.747 ASP0.256 Plastic 1.633 23.4 −1.03 11 1.097 ASP 0.047 12 Lens 6 0.638 ASP0.650 Plastic 1.514 56.8 1.30 13 8.806 ASP 0.419 14 IR-cut filter Plano0.210 Glass 1.517 64.2 — 15 Plano 0.339 16 Image Plano — Note: Referencewavelength is 587.6 nm (d-line).

TABLE 10 Aspheric Coefficients Surface # 1 2 3 4 6 7 k = −2.0725E−01−7.7056E−01 −8.9818E−01 −1.4271E+00 1.3871E+01 −7.4081E+00 A4 =5.4356E−01 1.0635E+00 5.9066E−01 1.3894E+00 1.5132E−01 −7.5658E−01 A6 =−3.7707E−01 5.0337E+00 −1.9431E−01 −5.0234E−01 1.2553E+00 9.1358E−01 A8= −8.1544E−01 −3.0709E+01 −3.2505E+00 2.2564E+01 −4.5976E+00 A10 =1.3551E+00 4.8092E+01 1.2352E+01 1.6644E+01 A12 = −8.4009E−01−2.4586E+01 −1.6255E+01 A14 = 2.4775E−01 A16 = −2.9100E−02 Surface # 8 910 11 12 13 k = −1.0000E+00 6.9670E−01 3.1445E+00 −2.6303E+01−8.0662E+00 −9.0000E+01 A4 = 2.7536E−01 −1.0297E+00 −9.8651E−01−7.5148E−01 −1.7347E−01 4.3570E−01 A6 = −1.4776E+00 2.1355E+008.0863E−01 1.7909E+00 −6.3705E−01 −9.8302E−01 A8 = 1.7478E+00−4.7271E+00 1.1921E−01 −2.5593E+00 2.2611E+00 9.3570E−01 A10 =−2.0969E+00 1.1722E+01 7.5234E−01 2.0751E+00 −3.8900E+00 −4.9009E−01 A12= −2.0367E+01 −6.9997E−01 3.2250E+00 1.0944E−01 A14 = 1.5358E+01−9.9070E−01

In the 5th embodiment, the equation of the aspheric surface profiles ofthe aforementioned lens elements is the same as the equation of the 1stembodiment. Also, the definitions of these parameters shown in thefollowing table are the same as those stated in the 1st embodiment withcorresponding values for the 5th embodiment, so an explanation in thisregard will not be provided again.

Moreover, these parameters can be calculated from Table 9 and Table 10as the following values and satisfy the following conditions:

5th Embodiment f [mm] 1.30 T12/(T34 + T45 + T56) 2.35 Fno 2.67TL/sin(HFOV × 1.6) [mm] 4.74 HFOV [deg.] 58.6 CT5/|Sag52| 21.11tan(HFOV) 1.64 R11/f 0.49 Nmax 1.633 |f1|/f2 0.08 T12/T23 1.82 f6/f40.57

Furthermore, according to the 5th embodiment, when a central thicknessof the first lens element 510 is CT1, a central thickness of the secondlens element 520 is CT2, a central thickness of the third lens element530 is CT3, a central thickness of the fourth lens element 540 is CT4,and a central thickness of the sixth lens element 560 is CT6, thefollowing conditions are satisfied: CT1<CT2; CT1<CT3; CT1<CT4; andCT1<CT6.

According to the 5th embodiment, when the focal length of the first lenselement 510 is f1, the focal length of the second lens element 520 isf2, a focal length of the third lens element 530 is f3, the focal lengthof the fourth lens element 540 is f4, a focal length of the fifth lenselement 550 is f5, and the focal length of the sixth lens element 560 isf6, the following conditions are satisfied: |f5|<|f1|; |f5|<|f2|;|f5|<|f3|; |f5|<|f4|; and |f5|<|f6|.

6th Embodiment

FIG. 11 is a schematic view of an image capturing device according tothe 6th embodiment of the present disclosure. FIG. 12 shows sphericalaberration curves, astigmatic field curves and a distortion curve of theimage capturing to device according to the 6th embodiment. In FIG. 11,the image capturing device includes an optical lens (its referencenumeral is omitted) and an image sensor 690. The optical lens includes,in order from an object side to an image side, a first lens element 610,a second lens element 620, an aperture stop 600, a third lens element630, a fourth lens element 640, a fifth lens element 650, a sixth lenselement 660, an IR-cut filter 670 and an image surface 680, wherein theimage sensor 690 is disposed on the image surface 680 of the opticallens. The optical lens has a total of sixth lens elements (610-660) withrefractive power, and there is an air space between every two lenselements of the first lens element 610, the second lens element 620, thethird lens element 630, the fourth lens element 640, the fifth lenselement 650 and the sixth lens element 660 that are adjacent to eachother.

The first lens element 610 with negative refractive power has anobject-side surface 611 being convex in a paraxial region thereof and animage-side surface 612 being concave in a paraxial region thereof. Thefirst lens element 610 is made of plastic material, and has theobject-side surface 611 and the image-side surface 612 being bothaspheric.

The second lens element 620 with positive refractive power has anobject-side surface 621 being convex in a paraxial region thereof and animage-side surface 622 being concave in a paraxial region thereof. Thesecond lens element 620 is made of plastic material, and has theobject-side surface 621 and the image-side surface 622 being bothaspheric.

The third lens element 630 with positive refractive power has anobject-side surface 631 being concave in a paraxial region thereof andan image-side surface 632 being convex in a paraxial region thereof. Thethird lens element 630 is made of plastic material, and has theobject-side surface 631 and the image-side surface 632 being bothaspheric.

The fourth lens element 640 with positive refractive power has anobject-side surface 641 being convex in a paraxial region thereof, andan image-side surface 642 being convex in a paraxial region thereof andincluding at least one concave shape in an off-axis region thereof. Thefourth lens element 640 is made of plastic material, and has theobject-side surface 641 and the image-side surface 642 being bothaspheric.

The fifth lens element 650 with negative refractive power has anobject-side surface 651 being concave in a paraxial region thereof, andan image-side surface 652 being concave in a paraxial region thereof andincluding at least one convex shape in an off-axis region thereof. Thefifth lens element 650 is made of plastic material, and has theobject-side surface 651 and the image-side surface 652 being bothaspheric.

The sixth lens element 660 with positive refractive power has anobject-side surface 661 being convex in a paraxial region thereof, andan image-side surface 662 being concave in a paraxial region thereof andincluding at least one convex shape in an off-axis region thereof. Thesixth lens element 660 is made of plastic material, and has theobject-side surface 661 and the image-side surface 662 being bothaspheric.

The IR-cut filter 670 is made of glass material and located between thesixth lens element 660 and the image surface 680, and will not affect afocal length of the optical lens.

The detailed optical data of the 6th embodiment are shown in Table 11and the aspheric surface data are shown in Table 12 below.

TABLE 11 6th Embodiment f = 1.02 mm, Fno = 2.45, HFOV = 60.8 deg.Curvature Focal Surface # Radius Thickness Material Index Abbe # Length0 Object Plano Infinity 1 Lens 1 1.401 ASP 0.299 Plastic 1.544 55.9−1.68 2 0.511 ASP 0.646 3 Lens 2 1.392 ASP 0.313 Plastic 1.639 23.5 8.354 1.718 ASP 0.215 5 Ape. Stop Plano 0.009 6 Lens 3 −27.171 ASP 0.391Plastic 1.544 55.9 1.72 7 −0.910 ASP 0.030 8 Lens 4 6.707 ASP 0.694Plastic 1.544 55.9 1.35 9 −0.793 ASP 0.050 10 Lens 5 −0.732 ASP 0.255Plastic 1.639 23.5 −1.12 11 31.702 ASP 0.169 12 Lens 6 0.892 ASP 0.716Plastic 1.544 55.9 1.75 13 9.800 ASP 0.400 14 IR-cut filter Plano 0.175Glass 1.517 64.2 — 15 Plano 0.144 16 Image Plano — Note: Referencewavelength is 587.6 nm (d-line).

TABLE 12 Aspheric Coefficients Surface # 1 2 3 4 6 7 k = −7.2280E−01−8.2265E−01 1.0556E+00 −1.6190E−01 −1.6902E+00 −3.7511E+00 A4 =4.5660E−01 1.2387E+00 2.6898E−01 7.2144E−01 −8.1192E−02 −8.0299E−01 A6 =−8.9294E−01 −1.8232E+00 −7.0173E−01 1.1657E+00 −1.0288E+00 8.1596E−01 A8= 6.6692E−01 −1.8477E+00 4.1425E+00 −9.7803E+00 A10 = −2.3791E−015.1098E+00 −1.4525E+01 1.6998E+01 A12 = 3.4841E−02 −3.6346E+001.0261E+01 Surface # 8 9 10 11 12 13 k = 2.8629E+01 −2.0402E−01−3.7018E−01 −4.6244E+01 −9.0434E+00 2.5798E+01 A4 = 9.2036E−033.4702E−01 4.9769E−01 −8.4049E−01 1.3285E−01 6.5205E−01 A6 = 1.9368E−01−4.1459E+00 −2.4155E+00 3.7007E+00 −1.2879E+00 −1.7680E+00 A8 =−3.1301E+00 1.5437E+01 3.4205E+00 −9.3997E+00 2.8636E+00 2.3002E+00 A10= 4.8334E+00 −2.7104E+01 1.3466E+01 −3.4864E+00 −1.7911E+00 A12 =1.9704E+01 −1.0021E+01 2.0658E+00 8.0827E−01 A14 = 3.0873E+00−4.5765E−01 −1.9367E−01 A16 = 1.9083E−02

In the 6th embodiment, the equation of the aspheric surface profiles ofthe aforementioned lens elements is the same as the equation of the 1stembodiment. Also, the definitions of these parameters shown in thefollowing table are the same as those stated in the 1st embodiment withcorresponding values for the 6th embodiment, so an explanation in thisregard will not be provided again.

Moreover, these parameters can be calculated from Table 11 and Table 12as the following values and satisfy the following conditions:

6th Embodiment f [mm] 1.02 T12/(T34 + T45 + T56) 2.59 Fno 2.45TL/sin(HFOV × 1.6) [mm] 4.54 HFOV [deg.] 60.8 CT5/|Sag52| 5.26 tan(HFOV)1.79 R11/f 0.87 Nmax 1.639 |f1|/f2 0.20 T12/T23 2.88 f6/f4 1.30

Furthermore, according to the 6th embodiment, when a central thicknessof the first lens element 610 is CT1, a central thickness of the secondlens element 620 is CT2, a central thickness of the third lens element630 is CT3, a central thickness of the fourth lens element 640 is CT4,and a central thickness of the sixth lens element 660 is CT6, thefollowing conditions are satisfied: CT1<CT2; CT1<CT3; CT1<CT4; andCT1<CT6.

According to the 6th embodiment, when the focal length of the first lenselement 610 is f1, the focal length of the second lens element 620 isf2, a focal length of the third lens element 630 is f3, the focal lengthof the fourth lens element 640 is f4, a focal length of the fifth lenselement 650 is f5, and the focal length of the sixth lens element 660 isf6, the following conditions are satisfied: |f5|<|f1|; |f5|<|f2|;|f5|<|f3|; |f5|<|f4|; and |f5|<|f6|.

7th Embodiment

FIG. 13 is a schematic view of an image capturing device according tothe 7th embodiment of the present disclosure. FIG. 14 shows sphericalaberration curves, astigmatic field curves and a distortion curve of theimage capturing device according to the 7th embodiment. In FIG. 13, theimage capturing device includes an optical lens (its reference numeralis omitted) and an image sensor 790. The optical lens includes, in orderfrom an object side to an image side, a first lens element 710, a secondlens element 720, an aperture stop 700, a third lens element 730, afourth lens element 740, a fifth lens element 750, a sixth lens element760, an IR-cut filter 770 and an image surface 780, wherein the imagesensor 790 is disposed on the image surface 780 of the optical lens. Theoptical lens has a total of sixth lens elements (710-760) withrefractive power, and there is an air space between every two lenselements of the first lens element 710, the second lens element 720, thethird lens element 730, the fourth lens element 740, the fifth lenselement 750 and the sixth lens element 760 that are adjacent to eachother.

The first lens element 710 with negative refractive power has anobject-side surface 711 being convex in a paraxial region thereof and animage-side surface 712 being concave in a paraxial region thereof. Thefirst lens element 710 is made of plastic material, and has theobject-side surface 711 and the image-side surface 712 being bothaspheric.

The second lens element 720 with positive refractive power has anobject-side surface 721 being convex in a paraxial region thereof and animage-side surface 722 being concave in a paraxial region thereof. Thesecond lens element 720 is made of plastic material, and has theobject-side surface 721 and the image-side surface 722 being bothaspheric.

The third lens element 730 with positive refractive power has anobject-side surface 731 being concave in a paraxial region thereof andan image-side surface 732 being convex in a paraxial region thereof. Thethird lens element 730 is made of plastic material, and has theobject-side surface 731 and the image-side surface 732 being bothaspheric.

The fourth lens element 740 with positive refractive power has anobject-side surface 741 being convex in a paraxial region thereof, andan image-side surface 742 being convex in a paraxial region thereof andincluding at least one concave shape in an off-axis region thereof. Thefourth lens element 740 is made of plastic material, and has theobject-side surface 741 and the image-side surface 742 being bothaspheric.

The fifth lens element 750 with negative refractive power has anobject-side surface 751 being concave in a paraxial region thereof, andan image-side surface 752 being concave in a paraxial region thereof andincluding at least one convex shape in an off-axis region thereof. Thefifth lens element 750 is made of plastic material, and has theobject-side surface 751 and the image-side surface 752 being bothaspheric.

The sixth lens element 760 with positive refractive power has anobject-side surface 761 being convex in a paraxial region thereof, andan image-side surface 762 being concave in a paraxial region thereof andincluding at least one convex shape in an off-axis region thereof. Thesixth lens element 760 is made of plastic material, and has theobject-side surface 761 and the image-side surface 762 being bothaspheric.

The IR-cut filter 770 is made of glass material and located between thesixth lens element 760 and the image surface 780, and will not affect afocal length of the optical lens.

The detailed optical data of the 7th embodiment are shown in Table 13and the aspheric surface data are shown in Table 14 below.

TABLE 13 7th Embodiment f = 1.29 mm, Fno = 2.45, HFOV = 53.6 deg.Curvature Focal Surface # Radius Thickness Material Index Abbe # Length0 Object Plano Infinity 1 Lens 1 1.053 ASP 0.419 Plastic 1.639 23.5−2.35 2 0.523 ASP 0.645 3 Lens 2 0.954 ASP 0.372 Plastic 1.639 23.5 5.764 1.092 ASP 0.179 5 Ape. Stop Plano 0.015 6 Lens 3 −24.558 ASP 0.388Plastic 1.544 55.9 1.72 7 −0.906 ASP 0.030 8 Lens 4 64.598 ASP 0.627Plastic 1.544 55.9 1.52 9 −0.836 ASP 0.088 10 Lens 5 −0.800 ASP 0.255Plastic 1.639 23.5 −1.23 11 64.792 ASP 0.234 12 Lens 6 0.866 ASP 0.508Plastic 1.544 55.9 1.76 13 6.981 ASP 0.400 14 IR-cut filter Plano 0.175Glass 1.517 64.2 — 15 Plano 0.165 16 Image Plano — Note: Referencewavelength is 587.6 nm (d-line).

TABLE 14 Aspheric Coefficients Surface # 1 2 3 4 6 7 k = −7.9961E−01−9.2372E−01 −4.6981E−01 −2.0572E+00 9.0000E+01 −3.0190E+00 A4 =2.6704E−01 1.0873E+00 1.8226E−01 7.4636E−01 −1.9195E−01 −8.2824E−01 A6 =−3.2493E−01 −2.7674E+00 −3.2860E−01 2.9591E+00 4.1991E−01 1.7562E+00 A8= 1.0129E−01 4.0804E+00 1.8865E+00 −9.2903E+00 −8.4388E+00 −1.5303E+01A10 = −3.8568E−03 −4.7303E+00 −2.4587E+00 6.0727E+01 6.1832E+012.9506E+01 A12 = 2.4739E−04 2.1348E+00 −8.2400E+00 4.6348E−11 5.9171E−101.0882E−09 Surface # 8 9 10 11 12 13 k = −9.0000E+01 −2.0058E−01−1.6410E−01 −1.0507E+01 −8.7735E+00 4.1138E+00 A4 = −8.8337E−025.8338E−01 6.6686E−01 −9.5887E−01 3.3671E−01 1.0091E+00 A6 = 7.7324E−01−4.6822E+00 −2.4441E+00 3.8936E+00 −2.0298E+00 −2.9874E+00 A8 =−5.8411E+00 1.5718E+01 3.9527E+00 −9.1121E+00 3.6087E+00 4.2223E+00 A10= 8.1400E+00 −2.7369E+01 −7.9834E−01 1.2486E+01 −3.4418E+00 −3.5670E+00A12 = −4.1564E−09 1.9704E+01 −1.2242E−08 −8.9961E+00 1.6617E+001.7981E+00 A14 = 2.6433E+00 −3.1052E−01 −5.0383E−01 A16 = 6.0912E−02

In the 7th embodiment, the equation of the aspheric surface profiles ofthe aforementioned lens elements is the same as the equation of the 1stembodiment. Also, the definitions of these parameters shown in thefollowing table are the same as those stated in the 1st embodiment withcorresponding values for the 7th embodiment, so an explanation in thisregard will not be provided again.

Moreover, these parameters can be calculated from Table 13 and Table 14as the following values and satisfy the following conditions:

7th Embodiment f [mm] 1.29 T12/(T34 + T45 + T56) 1.83 Fno 2.45TL/sin(HFOV × 1.6) [mm] 4.51 HFOV [deg.] 53.6 CT5/|Sag52| 4.57 tan(HFOV)1.36 R11/f 0.67 Nmax 1.639 |f1|/f2 0.41 T12/T23 3.32 f6/f4 1.16

Furthermore, according to the 7th embodiment, when the focal length ofthe first lens element 710 is f1, the focal length of the second lenselement 720 is f2, a focal length of the third lens element 730 is f3,the focal length of the fourth lens element 740 is f4, a focal length ofthe fifth lens element 750 is f5, and the focal length of the sixth lenselement 760 is f6, the following conditions are satisfied: |f5|<|f1|;|f5|<|f2|; |f5|<|f3|; |f5|<|f4|; and |f5|<|f6|.

8th Embodiment

FIG. 16 is a schematic view of an electronic device 10 according to the8th embodiment of the present disclosure. The electronic device 10 ofthe 8th embodiment is a smart phone, wherein the electronic device 10includes an image capturing device 11. The image capturing device 11includes an optical lens (its reference numeral is omitted) according tothe present disclosure and an image sensor (its reference numeral isomitted), wherein the image sensor is disposed on an image surface ofthe optical lens.

9th Embodiment

FIG. 17 is a schematic view of an electronic device 20 according to the9th embodiment of the present disclosure. The electronic device 20 ofthe 9th embodiment is a tablet personal computer, wherein the electronicdevice 20 includes an image capturing device 21. The image capturingdevice 21 includes an optical lens (its reference numeral is omitted)according to the present disclosure and an image sensor (Its referencenumeral is omitted), wherein the image sensor is disposed on an imagesurface of the optical lens.

10th Embodiment

FIG. 18 is a schematic view of an electronic device 30 according to the10th embodiment of the present disclosure. The electronic device 30 ofthe 10th embodiment is a wearable device, such as a head-mounted display(HMD), wherein the electronic device 30 includes an image capturingdevice 31. The image capturing device 31 includes an optical lens (itsreference numeral is omitted) according to the present disclosure and animage sensor (its reference numeral is omitted), wherein the imagesensor is disposed on an image surface of the optical lens.

The foregoing description, for purpose of explanation, has beendescribed with reference to specific embodiments. It is to be noted thatTABLES 1-14 show different data of the different embodiments; however,the data of the different embodiments are obtained from experiments. Theembodiments were chosen and described in order to best explain theprinciples of the disclosure and its practical applications, to therebyenable others skilled in the art to best utilize the disclosure andvarious embodiments with various modifications as are suited to theparticular use contemplated. The embodiments depicted above and theappended drawings are exemplary and are not intended to be exhaustive orto limit the scope of the present disclosure to the precise formsdisclosed. Many modifications and variations are possible in view of theabove teachings.

What is claimed is:
 1. An optical lens comprising, in order from anobject side to an image side: a first lens element with negativerefractive power having an image-side surface being concave in aparaxial region thereof; a second lens element with positive refractivepower having an object-side surface being convex in a paraxial regionthereof; a third lens element with positive refractive power having anobject-side surface being convex in a paraxial region thereof; a fourthlens element having positive refractive power; a fifth lens elementhaving negative refractive power; and a sixth lens element with positiverefractive power having an object-side surface being convex in aparaxial region thereof and an image-side surface being concave in aparaxial region thereof, the image-side surface of the sixth lenselement comprising at least one convex shape in an off-axis regionthereof, and the object-side surface and the image-side surface of thesixth lens element being aspheric; wherein the optical lens has a totalof six lens elements, an axial distance between the first lens elementand the second lens element is T12, an axial distance between the secondlens element and the third lens element is T23, and the followingcondition is satisfied:1.40<T12/T23.
 2. The optical lens of claim 1, wherein an absolute valueof a curvature radius of the object-side surface of the third lenselement is greater than an absolute value of a curvature radius of animage-side surface the of third lens element.
 3. The optical lens ofclaim 1, wherein an absolute value of a curvature radius of anobject-side surface of the fifth lens element is greater than anabsolute value of a curvature radius of an image-side surface the offifth lens element.
 4. The optical lens of claim 1, wherein the fourthlens element is a meniscus lens element.
 5. The optical lens of claim 1,wherein a central thickness of the first lens element is CT1, a centralthickness of the second lens element is CT2, and the following conditionis satisfied:CT1<CT2.
 6. The optical lens of claim 1, wherein a focal length of thefirst lens element is f1, a focal length of the second lens element isf2, a focal length of the third lens element is f3, a focal length ofthe fourth lens element is f4, a focal length of the fifth lens elementis f5, a focal length of the sixth lens element is f6, and the followingconditions are satisfied:|f5|<|f1||f5|<|f2|;|f5|<|f3|;|f5|<|f4|; and|f5|<|f6|.
 7. The optical lens of claim 1, wherein a refractive index ofthe first lens element is N1, a refractive index of the second lenselement is N2, a refractive index of the third lens element is N3, arefractive index of the fourth lens element is N4, a refractive index ofthe fifth lens element is N5, a refractive index of the sixth lenselement is N6, a maximum of N1, N2, N3, N4, N5 and N6 is Nmax, and thefollowing condition is satisfied:1.60<Nmax<1.70.
 8. The optical lens of claim 1, wherein a focal lengthof the optical lens is f, a curvature radius of the object-side surfaceof the sixth lens element is R11, and the following condition issatisfied:0<R11/f<1.40.
 9. The optical lens of claim 1, wherein a half of themaximal field of view of the optical lens is HFOV, and the followingcondition is satisfied:1.30<tan(HFOV).
 10. The optical lens of claim 1, wherein there is an airspace between every two lens elements of the first lens element, thesecond lens element, the third lens element, the fourth lens element,the fifth lens element and the sixth lens element that are adjacent toeach other.
 11. The optical lens of claim 1, wherein a focal length ofthe first lens element is f1, a focal length of the second lens elementis f2, and the following condition is satisfied:0.10≤|f1|/f2<4.0.
 12. The optical lens of claim 1, wherein the axialdistance between the first lens element and the second lens element isT12, an axial distance between the third lens element and the fourthlens element is T34, an axial distance between the fourth lens elementand the fifth lens element is T45, an axial distance between the fifthlens element and the sixth lens element is T56, and the followingcondition is satisfied:1.25<T12/(T34+T45+T56)<4.0.
 13. The optical lens of claim 1, wherein ahalf of the maximal field of view of the optical lens is HFOV, an axialdistance between an object-side surface of the first lens element and animage surface is TL, and the following condition is satisfied:TL/sin(HFOV×1.6)<7.0 mm.
 14. The optical lens of claim 1, wherein anobject-side surface of the fourth lens element comprises at least oneconcave shape in an off-axis region thereof.
 15. The optical lens ofclaim 1, wherein a central thickness of the fourth lens element isgreater than a central thickness of the third lens element.
 16. Theoptical lens of claim 1, wherein a central thickness of the fifth lenselement is greater than an axial distance between the fifth lens elementand the sixth lens element.
 17. An image capturing device, comprising:the optical lens of claim 1; and an image sensor, wherein the imagesensor is disposed on an image surface of the optical lens.
 18. Anelectronic device, comprising: the image capturing device of claim 17.